System and method for storage of electronic mail

ABSTRACT

A method of storage of an e-mail includes either receiving the e-mail at a portable electronic device or sending the e-mail from the portable electronic device. The e-mail is marked for saving at the portable electronic device and transmitted by radio communication for receipt by a server and for storage of the e-mail in a backup database.

FIELD

The present application relates generally to electronic devices and to asystem and method for storage of electronic mail.

BACKGROUND

Portable electronic devices such as wireless personal digital assistants(PDAs), smart telephones and laptop computers with wireless capabilitieshave gained widespread use for a variety of functions. Such devices arecommonly used for communication purposes including transportation ofdata, and run on a wide variety of networks from data-only networks suchas Mobitex and DataTAC to complex voice and data networks such asGSM/GPRS, CDMA, EDGE, UMTS and CDMA 2000 networks.

These portable electronic devices are commonly used for communication,for example, for sending and receiving electronic mail (e-mail), SMSmessages (short message service, commonly referred to as text messages)and PIN messages (Personal Identification Number messages). Forvoice-enabled devices such as smart telephones for example, voicecommunication in the form of telephone calls can be initiated andreceived at the portable electronic devices.

Copies of e-mail messages sent and received are stored in a third-partydatabase such as an Exchange™ database controlled by a server, forexample, an Exchange™ server. During synchronization of a portableelectronic device with a communication system connected to the Exchangeserver through a connector, the status of e-mails is synchronized aswell as the folder in which e-mails are filed. For example, e-mails thatare opened at the portable electronic device are deemed to be opened atthe database. Changes in status such as a change from unopened to openedare therefore synchronized. With the exception of synchronization of thestatus of e-mails on the portable electronic device, e-mails on theExchange™ database are not locally controlled by the portable electronicdevice.

BRIEF DESCRIPTION OF THE DRAWINGS

The system and method for communication record logging will be betterunderstood with reference to the following description and to theFigures, in which:

FIG. 1 is a functional block diagram of a communication system andportable electronic device for storage of electronic mail in accordancewith one embodiment;

FIG. 2 is a block diagram of certain components within the electronicdevice of FIG. 1;

FIG. 3 is a block diagram of certain components within thesynchronization server of FIG. 1;

FIG. 4 is a sequence diagram illustrating functions carried out at boththe portable electronic device and the communication system of FIG. 1,during storage of electronic mail according to one example;

FIG. 5 shows a menu screen of an LCD display of the electronic device ofFIG. 1;

FIG. 6 shows a list of electronic mail messages screen of the LCDdisplay of the electronic device of FIG. 1;

FIG. 7 shows a list of electronic mail messages including a submenuscreen of the LCD display of the electronic device of FIG. 1;

FIG. 8 is a sequence diagram illustrating functions carried out at boththe portable electronic device and the communication system of FIG. 1,during storage of electronic mail according to another example;

FIG. 9 shows a list of saved electronic mail messages including asubmenu screen of the LCD display of the electronic device of FIG. 1;

FIG. 10 is a sequence diagram illustrating functions carried out at boththe portable electronic device and the communication system of FIG. 1during removal of an electronic mail message from storage according toone example; and

FIG. 11 is a sequence diagram illustrating functions carried out at boththe portable electronic device and the communication system of FIG. 1during restore of electronic mail to the portable electronic device ofFIG. 1.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference is first made to FIG. 1, which shows a functional blockdiagram of a communication system indicated generally by the numeral 20and a portable electronic device 22. The communication system 20provides for communications with portable electronic devices includingthe exemplary portable electronic device 22, as shown. The portableelectronic device 22 and the communication system 20 are operable toeffect communications over a radio communications channel therebetween.Data originating at the portable electronic device 22 is communicated tothe communication system 20 by way of the radio communications channel.Similarly, data originating at the communication system 20 iscommunicated from the communication system 20 to the portable electronicdevice 22 by way of the radio communications channel, thereby providingdata to the portable electronic device 22.

For the purpose of illustration, the communication system 20 isfunctionally represented in FIG. 1 and a single base station 24 isshown. The base station 24 defines a coverage area, or cell 26 withinwhich communications between the base station 24 and the portableelectronic device 22 can be effectuated. It will be appreciated that theportable electronic device 22 is movable within the cell 26 and can bemoved to coverage areas defined by other cells that are not illustratedin the present example. The communication system 20 includes a basestation 24 that is part of a wireless network and infrastructure 28 thatprovides a link to the portable electronic device 22. The wirelessnetwork and infrastructure 28 includes a number of base stations (notshown) that provide the other cells referred to above. Data is deliveredto the portable electronic device 22 via wireless transmission from thebase station 24. Similarly, data is sent from the portable electronicdevice 22 via wireless transmission to the base station 24.

Wireless networks and infrastructures include, for example, data-centricwireless networks, voice-centric wireless networks, or dual-modewireless networks. For the purpose of the present exemplary embodiment,the wireless network and infrastructure 28 includes a dual-mode wirelessnetwork that supports both voice and data communications over the samephysical base stations.

The communication system 20 includes a relay device 30 that is connectedto the Internet 29 that is, in turn, connected to the wireless networkand infrastructure 28. The relay device 30 is also connected to a server32. It will be understood that the functions provided by the relaydevice 30 and the server 32 can be embodied in the same device. Theserver 32 is also connected to an administration server 34, as shown.The administration server 34 provides administrative services to andcontrol over the server 32.

The server 32 is functionally coupled to an e-mail (for example,Exchange™) connector 37 for a third party database (for example, anExchange-based database) 39. The connector 37 receives commands from theserver 32. It will be understood that the connector 37 is a functionalcomponent and can be provided by way of an application on the server 32.Copies of e-mail messages sent from and received at the portableelectronic device 22 are stored in the third-party database 39. Duringsynchronization of the third-party database 39 and the portableelectronic device 22, only status changes of e-mail messages aresynchronized such that the status of e-mail messages at the portableelectronic device 22 match the status of the e-mail message copiesstored at the third-party database.

The server 32 is also functionally coupled through a backup/restoreconnector 36 to a backup/restore database 38. Other connectors anddatabases can be provided, for example, for synchronization purposes.For the purpose of simplicity, such connectors and databases are notshown in FIG. 1. The connector 36 receives commands from the server 32.Again, it will be understood that the connector 36 is a functionalcomponent and can be provided by way of an application on the server 32.The backup/restore database 38 is used for storing data records,including, for example, copies of e-mail messages sent from the portableelectronic device 22 and received at the portable electronic device 22.

Referring now to FIG. 2, a block diagram of certain components withinthe portable electronic device 22 is shown. In the present embodiment,the portable electronic device 22 is based on the computing environmentand functionality of a wireless personal digital assistant. It will beunderstood, however, that the portable electronic device 22 is notlimited to a wireless personal digital assistant. Other portableelectronic devices are possible, such as cellular telephones, smarttelephones, and laptop computers. Referring again to the presentembodiment, the portable electronic device 22 is based on amicrocomputer including a processor 40 connected to a read-only memory(ROM) 42 that contains a plurality of applications including, forexample, an e-mail messaging application, a Web browser application, anaddress book application, a tasks application, a memo pad, a calendarapplication and others. The applications are executable by the processor40 to enable the portable electronic device 22 to perform certainfunctions including, for example, e-mail message functions. Theprocessor 40 is also connected to a random access memory (RAM) unit 44and a persistent storage device 46 which are responsible for variousnon-volatile storage functions of the portable electronic device 22. Theprocessor 40 receives input from various input devices including akeypad 48 and a trackwheel 49 or trackball (not shown). The processor 40outputs to various output devices including an LCD display 50 and aspeaker 52. A microphone 54 and phone speaker 56 are connected to theprocessor 40 for cellular telephone functions. The processor 40 is alsoconnected to an internal clock 58 and a modem and radio device 60. Themodem and radio device 60 is used to connect to wireless networks usingan antenna 62. The modem and radio device 60 transmits and receivesvoice and data communications to and from the portable electronic device22 through the antenna 62.

The portable electronic device 22 is operable to effect two-waycommunication of voice and data. Thus, the portable electronic device 22transmits and receives voice communications over the wireless networkand infrastructure 28 via wireless communications with the base station24 over a radio communications channel. Similarly, the portableelectronic device 22 transmits and receives data communications over thewireless network and infrastructure 28 via wireless radio communicationswith the base station 24 over a radio communications channel.

Reference is now made to FIG. 3 which shows a block diagram of certaincomponents within the server 32. Similar to the portable electronicdevice 22, the server 32 includes a processor 66 connected to aread-only memory (ROM) 68 that includes applications executable by theprocessor 66 and enables the server 32 to perform certain functionsincluding backing up data from the portable electronic device 22. Theprocessor 66 is also connected to a random access memory (RAM) unit70and a persistent storage device 72 which are responsible for variousstorage functions of the server 32.

It will be understood that the functions described herein can be carriedout in any suitable manner. In the present example, the functions arecarried out by algorithms executable by the processor 66. For example,the processor 66 of the server 32 is operable to receive communicationsgenerated by the portable electronic device 22 for delivery to otherelectronic devices. The processor 66 is operable to store e-mailmessages in a backup/restore table in a backup/restore database and todelete the e-mail messages from the backup database.

The portable electronic device 22 is operable to send and receive avariety of different communication types including e-mail messages fromother portable electronic devices (not shown) connected to the wirelessnetwork and infrastructure 28.

It will be appreciated that the portable electronic device 22 and server32 are operable to carry out many other functions, some of which aredescribed below.

Reference is now made to FIG. 4, which shows a sequence diagramillustrating functions carried out at both the portable electronicdevice 22 and the communication system 20 for storage of electronic mailaccording to one example of an embodiment of the present application.Coding of software for carrying out the steps illustrated is well withinthe scope of a person of ordinary skill in the art. In the presentexample, an e-mail message is received at the portable electronic device22, from another electronic device. The e-mail message is composed andsent from the other electronic device (not shown) connected through theinternet 29 and the relay 30 to the server 32. The e-mail message isreceived at the server 32 at step 100. A copy of the e-mail message isforwarded and stored in the Exchange™ database 39, as will be understoodby those skilled in the art. A copy of the e-mail message is alsoprocessed by the server 32 for transmission to the portable electronicdevice 22 and routed from the server 32, through the relay 30, theInternet 29 and the wireless network and infrastructure 28, to the basestation 24 for transmission via a radio communication channel to theportable electronic device 22 at step 102. It will be appreciated thatthe e-mail message is forwarded to the base station 24 covering the cellin which the portable electronic 22 device is located.

The e-mail message is received at the portable electronic device 22 atstep 104. In the present example, the portable electronic device emits anotification such as an e-mail-specific ring tone through the speaker52, thereby notifying the user of receipt of an e-mail message at theportable electronic device 22. Referring to FIG. 5, there is shown anexemplary menu screen that is displayed on the LCD display 50 of theportable electronic device 22. The exemplary menu screen includes adisplay clock that is updated according to the internal clock 58, andapplications including an e-mail Messaging application, a Web browser,an Address book, a Tasks application, a Memo application and a Calendar,The user views the e-mail message by scrolling through the applicationsusing the trackwheel 49 or a trackball and pressing inwardly on thetrackwheel 49 or trackball to select the e-mail messaging application.Selection of the e-mail messaging application causes execution of thee-mail messaging application and a list of e-mail messages is displayed,including previously sent and received, opened and unopened e-mailmessages that remain on the portable electronic device, as shown in theexemplary messaging applications screen of FIG. 6.

Upon selection of an unopened e-mail message from the menu list screen,a submenu is displayed on the LCD display 50, displaying differentoptions for user selection, including, for example, Open, Mark Opened,Save, Reply, Forward, Delete, Compose, View Saved Messages and Close.Referring, for exemplary purposes, to selection of the e-mail receivedat step 104, the selection of this e-mail gives rise to the submenuoptions Open, File, Mark Opened, Save, Reply, Forward, Delete, Compose,and Close, as shown in FIG. 7. Many of these options will be understoodby those skilled in the art. For example, selection of the Open optionopens the e-mail for viewing on the LCD display 50. Selection of theMark Opened option marks the e-mail as opened on the list of e-mailmessages screen of FIG. 6 and closes the submenu shown in FIG. 7,returning to the list of e-mail messages. Selection of the Reply optioninitiates a new reply e-mail composition that is automatically addressedto the sender of the selected e-mail and includes the same subject linein the e-mail header. Selection of the Forward option initiates a newforward e-mail composition that incorporates in the new subject line thee-mail header of the selected e-mail. Selection of the Delete optiondeletes the e-mail from the list of e-mail messages screen. Selection ofthe Compose option initiates a new e-mail composition. Selection of theClose option closes the e-mail application and returns control to themenu screen shown in FIG. 5. It will be appreciated that if an e-mailmessage marked as opened is selected, the Open and Mark Opened optionsare not provided in the submenu shown in FIG. 7. Instead, a Mark Closedoption is provided.

Selection of the Save option from the submenu options shown in FIG. 7marks the selected message as saved by changing an indicator, such as abit flag, on the e-mail such that during scheduled clean-up and memorymanagement options, the e-mail marked as saved remains on the portableelectronic device 22. Those e-mails not marked as saved are subject todeletion during clean-up and memory management operations. Such clean-upoperations can be regularly carried out, for example, based on age ofunmarked e-mail messages, based on the number of e-mail messages or sizeof e-mail messages in an “inbox” in the portable electronic device 22,or during low-memory conditions at the portable electronic device 22.Thus, an e-mail that is more than 60 days old, for example, and that isnot marked as saved, is deleted from the portable electronic device 22.The corresponding copy of the e-mail message stored in the Exchange™database 39 is not deleted when the e-mail is deleted from the portableelectronic device 22. It will be understood, however, that no furtherstatus updates are sent from the server to the portable electronicdevice 22. In this case the server is notified of the deletion on theportable electronic device 22 and therefore no further updates are sentfor a deleted message.

Referring again to FIG. 4, the e-mail message received at step 104 ismarked as saved at step 106 by user selection of the e-mail messagingapplication from the menu screen, followed by user selection of thee-mail message from the list of e-mail messages and user-selection ofthe Save option in the submenu, as described above. Upon selection ofthe Save option, the e-mail is marked as saved as described above and acopy of the saved e-mail is transmitted over a radio communicationchannel from the portable electronic device 22 for delivery to theserver 32 at step 108.

The e-mail message is received at the base station 24 at step 110 andforwarded through the wireless network and infrastructure 28, theinternet 29 and the relay 30 to the server 32 of the communicationsystem 20. The copy of the e-mail message is then stored by the server,in the backup/restore database 38 via the backup/restore connector 36.The copy of the e-mail message is stored in a backup/restore table onthe backup/restore database 38. This is accomplished by first retrievingthe backup/restore table from the backup/restore database 38 at step112. The table includes e-mail message data including the fields fromthe e-mail identified by length and unique tag numbers. Such fieldsinclude, for example information regarding the sender (e-mail source),the recipient, the length of the e-mail message, a time stamp, the bodyof the message, a unique numeric e-mail identifier and others. Theserver adds the information in the form of contiguous binary data to thebackup/restore table at step 114 and stores the table in thebackup/restore database at step 116.

Although the backup/restore table stored in the backup/restore database38 is not accessible to the user of the portable electronic device 22,the backup/restore database 38 is used to restore data to the portableelectronic device 22 in the event of loss of data at the portableelectronic device 22. Thus, in the event of memory loss at the portableelectronic device 22, a synchronization session is invoked and the datastored in the backup/restore database 38 is restored on the portableelectronic device 22, thereby restoring all e-mail records previouslymarked as saved by the user.

Reference is now made to FIG. 8, which shows a sequence diagramillustrating functions carried out at both the portable electronicdevice 22 and the communication system 20 for storage of electronic mailaccording to another example of an embodiment. Coding of software forcarrying out the steps illustrated is well within the scope of a personof ordinary skill in the art. In the present example, an e-mail messageis composed by the user of the portable electronic device 22 and sent toanother electronic device. In order to send an e-mail message using theportable electronic device 22, the e-mail messaging application isselected from the menu screen shown in FIG. 5, using the trackwheel 49,as described above with reference to the first-described exemplaryembodiment. For the purpose of the present example, the compose e-mailoption is chosen from the submenu screen shown in FIG. 7 after selectionof one of the e-mail messages in the list of e-mail messages. The e-mailis then composed using the keypad 48 (step 120). The destination e-mailaddress is entered and the message is sent by selection of a sendcommand from another submenu, using the trackwheel 49. The e-mailmessage is then sent via a radio communications channel to the basestation 24 (for the cell in which the portable electronic device 22 islocated) for delivery to the server 32, at step 122. Upon sending thee-mail from the portable electronic device 22, a copy of the e-mailmessage is maintained at the portable electronic device 22 and isdisplayed in the list of e-mail messages described with reference toFIG. 6 (step 124).

Referring again to FIG. 8, the e-mail message is received at the basestation 24 and forwarded through the wireless network and infrastructure28, the internet 29, and the relay 30, to the server 32 of thecommunication system 20 at step 126. A copy of the e-mail message isprocessed by the server 32 and forwarded and stored in the Exchange™database and the message is routed through the internet 29 for deliveryto the destination electronic device at step 128.

In the present example, the e-mail message that is maintained at theportable electronic device 22 is marked as saved at step 130 by userselection of the e-mail message from the list of e-mail messages anduser-selection of the Save option in the submenu, as described above.Upon selection of the Save option, the e-mail is marked as saved asdescribed above and a copy of the saved e-mail is transmitted over aradio communication channel from the portable electronic device 22 fordelivery to the server 32 at step 132.

The copy of the e-mail message is received at the base station 24 andforwarded through the wireless network and infrastructure 28, theInternet 29 and the relay 30 to the server 32 of the communicationsystem 20, at step 134. Upon receipt of the copy of the e-mail messageat the server 32, the backup/restore table is retrieved from thebackup/restore database 38 at step 136. Again, the server 32 extractse-mail information from individual fields of the copy of the e-mailmessage, adds the information to the backup/restore table at step 138and stores the table in the backup/restore database at step 140.

It will be appreciated that selection of the Save option from thesubmenu options shown in FIG. 7 marks the sent message as saved suchthat during scheduled clean-up and memory management options, the e-mailmarked as saved remains on the portable electronic device 22. Further,in the event of memory loss at the portable electronic device 22, asynchronization session can be invoked to restore the data stored in thebackup/restore database 38 to the portable electronic device 22, therebyrestoring all e-mail records previously marked as saved by the user.

Selection of the View Saved Messages option from the submenu of FIG. 7results in a list of e-mail messages marked as saved at the portableelectronic device 22. Thus, only those e-mail messages marked as savedare displayed.

Upon selection of a saved message from the list of e-mail messagesmarked as saved at the portable electronic device 22, a saved messagessubmenu is displayed on the LCD display 50, displaying different optionsfor user selection, including, for example, Open, Mark Opened, Reply,Forward, Delete, Compose, and Close. Referring, for exemplary purposes,to selection of the e-mail marked as saved in the embodiment describedabove with reference to FIG. 4, the selection of this e-mail gives riseto the saved messages submenu options, as shown in FIG. 9. Again, manyof these options will be understood by those skilled in the art and aredescribed above. It will also be appreciated that if an e-mail messagemarked as opened is selected, the Open and Mark Opened options are notprovided. Instead, a Mark Closed option is provided. In the presentexample, selection of the Delete option removes the saved message markby changing a bit flag on the e-mail message, resulting in removal ofthe saved message from the list of e-mail messages marked as saved atthe portable electronic device 22. The e-mail message is still displayedin the list of e-mail messages described above and shown in FIG. 6,however.

Selection of the Delete option from the saved messages submenu for theselected e-mail message marked as saved at the portable electronicdevice 22 also results in deletion of the e-mail message informationstored in the backup/restore table of the backup/restore database.Referring now to FIG. 10, a sequence diagram is shown which illustratesfunctions carried out at both the portable electronic device 22 and thecommunication system 20 during deletion of e-mail from thebackup/restore database according to one aspect of an embodiment. Codingof software for carrying out the steps illustrated is well within thescope of a person of ordinary skill in the art. The e-mail messagesaved, for example, at step 106 is then deleted from the saved messagesby user selection of the Delete option from the submenu of FIG. 9. Asdescribed, the e-mail message is deleted from the saved messages,changing the bit flag on the e-mail message and resulting in removal ofthe saved message from the list of e-mail messages marked as saved atthe portable electronic device 22. Upon selection of the Delete option,a delete message command is also transmitted over a radio communicationchannel from the portable electronic device 22 for delivery to theserver 32 at step 152.

The delete message command is received at the base station 24 andforwarded through the wireless network and infrastructure 28, theinternet 29 and the relay 30 to the server 32 of the communicationsystem 20, at step 154. The copy of the e-mail message previously storedby the server 32 in the backup/restore database 38 via thebackup/restore connector 36 is then deleted from the backup/restoretable. To delete the copy of the e-mail message, the backup/restoretable is retrieved from the backup/restore database 38 at step 156. Theserver 32 deletes the information related to the e-mail selected fordeletion in the saved messages, from the backup/restore table at step158 and stores the table in the backup/restore database at step 160.

With the e-mail message no longer marked as saved (deleted from thesaved messages menu), the e-mail message still exists on the portableelectronic device 22 and is displayed in the list of e-mail messagesdescribed above with reference to FIG. 6, until the e-mail message isdeleted from the list of e-mail messages by selection of the Deleteoption from the submenu described with reference to FIG. 7, or until thee-mail is deleted during a clean-up or memory management operation.

In the example described above with reference to FIG. 10, the e-mailmessage is removed from the saved messages prior to deletion of thee-mail message from the list of e-mail messages shown and described withreference to FIG. 6. The e-mail message can be deleted from the list ofe-mail messages by selection of the Delete option from the submenu ofFIG. 7, while still retaining the message in the saved messages list. Inthis case, a copy of the e-mail message is saved in a collection ofe-mail messages for which the parent e-mail message has been deleted.Therefore, the e-mail message is not displayed in the list of e-mailmessages of FIG. 7. When the user selects the View Saved Messages optionof FIG. 7, however, the saved messages list includes two collections ofsaved messages, including all those messages that are still present inthe list of e-mail messages of FIG. 6 that have been marked as saved,and all those messages saved in the collection of e-mail messages thathave been marked as saved and for which the parent e-mail message hasbeen deleted.

For those e-mail messages that are saved in the collection of e-mailmessages that have been marked as saved and for which the parent e-mailmessage has been deleted, the message does not appear in the list ofe-mail messages of FIG. 6. In this case, selection of the Delete optionin the saved messages submenu of FIG. 9 does not simply result inchanging the bit flag on the e-mail message. Instead, selection of theDelete option results in deletion of the e-mail from the portableelectronic device.

Reference is made to FIG. 11 to describe a restore operation to restoresaved messages to the portable electronic device 22. Coding of softwarefor carrying out such steps is well within the scope of a person ofordinary skill in the art. The portable electronic device 22 receives arestore trigger at step 170, by, for example, selection of a restoreoption on the LCD display device 50. It will be understood that such arestore operation is selected, for example, in the event that data islost from the portable electronic device 22. In response to receipt ofthe restore trigger, the processor 40 retrieves any e-mail messagerecords from the folder of the database on which the saved e-mailrecords are stored in the portable electronic device 22, at step 172.The processor 40 generates a record hash for each e-mail message markedas saved at the portable electronic device 22 and then generates a grouphash for the folder, based on the individual record hashes at step 174.Next, an initialize command is transmitted along with the group hash,from the portable electronic device 22 to the communication system 20over a radio communication channel, at step 176. The initialize commandinitiates the restore process at the server 32, identifies the e-mailbackup/restore database 38 for restoring and provides session stateinformation including a session state identifier. The portableelectronic device 22 then awaits a response from the communicationsystem 20.

The communication system 20 receives the initialize command along withthe group hash at step 178 by receipt at the base station 24. The basestation 24 forwards the initialize command and the group hash to theserver 32. As indicated above, the initialize command identifies thedatabase for restore and provides session state information includingthe session state identifier. A session is thereby started with theportable electronic device 22. In response to receipt of the initializecommand, the server 32 retrieves the backup/restore table stored in thebackup/restore database 38 via the backup/restore connector at step 180.Next, the processor 66 of the server 32 generates record hashes, eachrecord hash being generated from the fields of the individual e-mailrecords saved in the backup/restore table of the backup/restore database38. From the record hashes, a group hash, referred to herein as thelocally generated group hash, is generated at step 182. After generationof the locally generated group hash, the hash information of the grouphash received from the portable electronic device 22 is compared withthe hash information of the corresponding locally generated group hashat step 184. If the comparison of the hash information indicates thatthe saved e-mail records stored in the database 40 on the portableelectronic device 22 are not in mismatch with the corresponding e-mailrecords stored in the backup/restore table on the backup/restoredatabase 38, then a response is sent to the portable electronic device22 to terminate the backup/restore session at step 186.

The response is received at the portable electronic device 22 at step188 and the backup/restore session is terminated at step 190.

If, on the other hand, the comparison of the hash information indicatesthat the e-mail message records are in mismatch, then a request foradditional hash information is generated by the server 32 at step 192.The request for additional hash information is a request for hashinformation associated with the individual e-mail message records. Theadditional hash information is requested for each e-mail record of thee-mail messages marked as saved at the portable electronic device 22.After generation of the request for additional hash information, therequest is then transmitted to the portable electronic device 22 at step194.

Once the request for additional hash information is received at theportable electronic device 22 at step 196, each record hash generated atstep 174 is transmitted to the communication system 20 over the radiocommunication channel at step 198.

The additional hash information is received at the communication system20 and delivered to the server 32 at step 200. In response to receipt ofthe requested additional hash information, each hash generated for eachof the saved e-mail message records at step 174 is compared with acorresponding one of the locally generated hashes generated at step 182(step 202) and a determination is made as to which of the saved e-mailmessage records, requires restoring. Thus, e-mail message records thatare not present in the saved messages list on the portable electronicdevice 22 but are present in the backup/restore table and e-mail messagerecords in the backup/restore table that differ from those records atthe portable electronic device 22 are transmitted to the portableelectronic device 22 at step 204. These e-mail message records arereceived at the portable electronic device 22 at step 206 and at step208, the processor 40 of the portable electronic device 22 determinesfor each e-mail message record received, whether or not the e-mailmessage record exists in the saved messages list. If the e-mail messagerecord does not exist in the saved messages list, the processor 40 ofthe portable electronic device 22 determines at step 210 whether or notthe e-mail message record exists in the list of e-mail messages (shownin FIG. 6). If the e-mail message record does not exist in the list ofe-mail messages, the e-mail message is saved in the collection of e-mailmessages marked as saved for which the parent e-mail message has beendeleted (step 212), thereby restoring the e-mail message to the portableelectronic device 22. If, on the other hand, the e-mail message recorddoes exist in the list of e-mail messages, the e-mail message is markedas saved by changing the bit flag on the e-mail as referred to above(step 214). Thus, the e-mail message is again marked as saved at theportable electronic device 22.

If at step 208, it is determined that the e-mail message record doesexist in the saved messages list, the e-mail record present in thebackup/restore table is compared to the e-mail message record at theportable electronic device 22. If the size of the e-mail message recordis greater at the backup/restore table than that at the portableelectronic device 22, the processor proceeds to step 212 and saves thee-mail message in the collection of e-mail messages marked as saved forwhich the parent e-mail message has been deleted. If, on the other hand,the size of the e-mail message record is greater at the portableelectronic device 22 than that at the backup/restore table, then thee-mail message record is transmitted from the portable electronic device22 for delivery to the server 32 for overwriting to update thebackup/restore table at step 218. The e-mail message record is receivedat the server 32 at step 220 and the backup/restore table is updated atstep 222. It will be appreciated that the size of the e-mail message atthe portable electronic device 22 can be larger than the size of thee-mail message at the backup/restore table as a result of only portionsof messages being transmitted to the portable electronic device 22 toreduce data transmission and reduce the memory required for storage ofthe messages. Thus, only a first portion of a large message istransmitted until the user requests more of the message. After the userrequests more of the message, further message content is transmitted.When only a portion of the e-mail is received and the e-mail message issaved at step 106 of FIG. 4, for example, the portion that is receivedis transmitted at step 108 to the server 32 and stored at thebackup/restore table. If the user later requests more of the message atthe portable electronic device 22, further message content istransmitted to the portable electronic device 22 and the message at theportable electronic device 22 is larger than the message at thebackup/restore table.

While the embodiments described herein are directed to particularimplementations of the system and method for storage of electronic mail,it will be understood that modifications and variations to theseembodiments are possible. For example, the time period for which a savedmessage is stored in the backup/restore database or in the portableelectronic device can be limited. Also, e-mail messages can be separatedinto separate tables at the backup/restore database based, for example,on the folder that the e-mail occupies on the portable electronicdevice. Thus, e-mails from different folders on the portable electronicdevice are stored in different tables at the backup/restore database.E-mail messages can also be separated into separate tables at thebackup/restore database based on the service from which the e-mail isforwarded to the portable electronic device. Thus e-mail messagesoriginally addressed to two different e-mail addresses that areforwarded to the same portable electronic device are saved in twoseparate tables at the backup/restore database.

In the embodiments described above, the portable electronic devicetransmits the saved e-mail messages to the communication system forstorage by the server in the backup/restore database. It iscontemplated, however, that a unique identification of the e-mailmessage can be transmitted so that, upon receipt by the server, theserver retrieves the e-mail message from the Exchange™ database 39. If,however, the e-mail message cannot be retrieved, the server thenrequests transmission of the e-mail message from the portable electronicdevice. Advantageously, this reduces the amount of data transmittedwirelessly. Also, rather than the portable electronic device performingthe size comparison of e-mail messages as described in relation to step216, the portable electronic device can transmit a size of the e-mailmessage record when the record hash is transmitted for delivery to theserver. Thus, the size comparison is carried out by the server and thee-mail message is not transmitted to the portable electronic deviceuntil it is determined that the message is to be transmitted for storageat the portable electronic device.

It will be appreciated that the components of the portable electronicdevice are shown in FIG. 2 for exemplary purposes only. Other portableelectronic device components are possible. For example, rather than atrackwheel 49, as shown in FIG. 2 and referred to in the abovedescription, the portable electronic device 22 can include a trackball.The trackball can be depressed as a means to provide additionaluser-input. The microprocessor 40 receives input from the trackballwhich is used for user selection of features from a list or a table onthe LCD display 50 of the portable electronic device 22. Selection iscarried out by rolling the trackball to roll a cursor (or highlightedregion), for example, to the desired selection and pressing inwardly onthe trackball. The portable electronic device 22 also includes otherfeatures, such as a battery, that are not shown.

According to one aspect, there is provided a method of storage of ane-mail that includes either receiving the e-mail at a portableelectronic device or sending the e-mail from the portable electronicdevice. The e-mail is marked for saving at the portable electronicdevice and transmitted by radio communication for receipt by a serverand for storage of the e-mail in a backup database.

According to another aspect, there is provided a portable electronicdevice that includes a receiver and transmitter for receiving andtransmitting an e-mail; a display for displaying the e-mail; a userinput for marking the e-mail for storage; a memory for storage of thee-mail; and a processor coupled to the receiver, the display, the userinput and the memory. The processor causes the transmitter to transmitthe e-mail by radio communication for receipt by a server and storage ofthe e-mail in a backup database, in response to the e-mail being markedfor storage.

According to another aspect, there is provided a computer-readablemedium having computer-readable code embodied therein, for execution bya processor, for receiving an e-mail at a portable electronic device orsending the e-mail from the portable electronic device, marking thee-mail for saving, at the portable electronic device, and transmittingthe e-mail by radio communication for receipt by a sever and for storageof the e-mail in a backup database.

Advantageously, electronic mail messages stored at a portable electronicdevice can be saved such that saved e-mail messages are not subject tomemory management operations or clean-up operations. Thus, these e-mailmessages are retained in memory at the portable electronic device. Thee-mail messages are also backed up in a backup/restore database so thatthe saved e-mail messages can be restored to the portable electronicdevice if ever they are lost from the device memory.

Many modifications and variations may occur to those skilled in the art.All such modifications and variations are believed to be within thesphere and scope of the present application.

1. A method of storage of an e-mail comprising: one of receiving thee-mail at a portable electronic device and sending the e-mail from theportable electronic device; marking the e-mail for saving at theportable electronic device, to avoid deletion of the e-mail from amemory of the portable electronic device during a memory managementoperation, for at least a period of time; and transmitting the e-mail byradio communication for receipt by a sever and for storage of the e-mailin a backup database.
 2. The method according to claim 1, whereinmarking the e-mail comprises receiving a user-input for marking thee-mail and, in response, changing an e-mail storage status.
 3. Themethod according to claim 2, wherein marking the e-mail for savingcomprises providing an indicator on the e-mail, in response to receiptof the user-input, to thereby change the e-mail storage status.
 4. Themethod according to claim 3, wherein providing said indicator compriseschanging a bit flag on the e-mail in response to receipt of theuser-input to thereby change the e-mail storage status.
 5. The methodaccording to claim 1, comprising receiving the e-mail at the server andstoring the e-mail in a backup database.
 6. The method according toclaim 5, wherein storing the e-mail in the backup database comprisesstoring the e-mail in a table.
 7. The method according to claim 1,comprising synchronizing the backup database with the portableelectronic device after a memory loss at said portable electronicdevice.
 8. The method according to claim 7, wherein synchronizing thebackup database with the portable electronic device comprises restoringthe e-mail to the portable electronic device after loss of the e-mail atthe portable electronic device.
 9. The method according to claim 7,wherein synchronizing the backup database with the portable electronicdevice comprises comparing a size of the e-mail from the portableelectronic device with a size of the e-mail the backup database and, ifthe e-mail at the backup database is determined to be smaller in sizethan the e-mail at the portable electronic device, transmitting thee-mail from the portable electronic device for storage in the backupdatabase.
 10. The method according to claim 7, wherein synchronizing thebackup database with the portable electronic device comprises comparinga size of the e-mail from the portable electronic device with a size ofthe e-mail at the backup database and, if the e-mail at the backupdatabase is determined to be larger in size than the e-mail at theportable electronic device, saving the e-mail from the backup database,at the portable electronic device.
 11. The method according to claim 7,wherein synchronizing the backup database with the portable electronicdevice comprises determining whether or not the e-mail message exists ina list of messages at the portable electronic device and, if so, markingsaid e-mail message as saved.
 12. The method according to claim 11,wherein if said e-mail message does not exist in said list of messages,saving said message at said portable electronic device.
 13. The methodaccording to claim 11, wherein if said e-mail message does not exist insaid list of messages, saving said message in a collection of e-mailmessages marked as saved for which a parent e-mail message has beendeleted.
 14. A portable electronic device comprising: a receiver andtransmitter for receiving and transmitting an e-mail; a display fordisplaying the e-mail; a user input for marking the e-mail for saving toavoid deletion of the e-mail from a memory of the portable electronicdevice during a memory management operation, for at least a period oftime; and a memory for storage of the e-mail; a processor coupled to thereceiver, the display, the user input and the memory and operable tocause the transmitter to transmit the e-mail by radio communication forreceipt by a server and storage of the e-mail in a backup database, inresponse to the e-mail being marked for saving.
 15. A computer-readablemedium having computer-readable code embodied therein for execution by aprocessor, the computer-readable code for: one of receiving an e-mail ata portable electronic device and sending the e-mail from the portableelectronic device; marking the e-mail for saving at the portableelectronic device, to avoid deletion of the e-mail from a memory of theportable electronic device during a memory management operation, for atleast a period of time; and transmitting the e-mail by radiocommunication for receipt by a sever and for storage of the e-mail in abackup database.